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2. Asymptotic Behaviour and Stability Problems in Ordinary Differential Equations;Cesari,1963
3. Functional analysis and Galerkin's method;Cesari;Michigan Math. J.,1964
4. Functional Analysis, Nonlinear Differential Equations and the Alternative Method;Cesari,1976
5. Fixed Points and Topological Degree in Nonlinear Analysis;Cronin,1964